drm/amdgpu/gfx8: implement emit_rreg/wreg function

Implement emit_rreg/wreg function for kiq ring.

Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com>
Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
index fa1d569..70ab72c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.h
@@ -34,6 +34,7 @@ struct amdgpu_virt {
 	uint32_t caps;
 	struct amdgpu_bo *csa_obj;
 	uint64_t csa_vmid0_addr;
+	uint32_t		reg_val_offs;
 };
 
 #define AMDGPU_CSA_SIZE    (8 * 1024)